The larger gentleman in a '40

Simon · 02-13-04, 04:06 AM

Ok, ok, fat bloke then. What can be done to improve the room in a GTD 40? is it possible to remove seat runners or lower the floors slightly? does the GTD steering column move very slightly upwards? I'm going to have to look at a removable steering wheel and a Dr Atkins book I know, but any other advice to help me squeeze into my dream car would be greatly appreciated. [img]/ubbthreads/images/graemlins/confused.gif[/img]
Thanks

Malcolm · 02-13-04, 05:52 AM

To raise the steering wheel, I cut another 1/2 inch off above the dash where the column passes through. This allows it to be higher than it otherwise would and gives me a better driving position. It looks fine.

Running a seat without runners is also no problem so long as the seat is fairly fixed to the floor. If you are not using harnesses then make sure you have very good fixings. Often in race cars a harness will hold the driver and the seat in place.

Why not custom make a seat from polystyrene and gaffer tape? Or use the mold systems of poly beads and resin?

Tony Hunt · 02-13-04, 05:57 AM

Hi,
You have hit the first problem that large gentlemen encounter! The easiest solution is a footectomy, but that aside there are a number of things:
1. Removing the seat runners provides 7/8" of headroom. You will need to make a couple of adapter plates to bolt the seat directly into the car. These are lengths of 1¼" wide by 1/8" strip with the rear bolts welded on because you won't be able to get at them with the seat in. At the same time move the harness crutch strap bolt because you will otherwise end up sitting on it - endurable for about 5 minutes, as long as the car isn't moving!
2. Insert a Gurney Dome in the driver's door.
3. You will probably have to ditch the GTD pedals if your feet are too big for them. At the same time, convert to twin master cylinders with a brake balance bar.
I am having the latter two jobs done by Frank Catt at Wealden Engineering, because I haven't yet been able to drive my car safely since I bought it!
Also consider a detachable steering wheel, which makes getting in and out a lot easier.

Simon · 02-13-04, 06:22 AM

Malcom, Tony, good advice thank you

Malcolm · 02-13-04, 07:49 AM

My seats are on runners. They are GTD supplied seats. If I removerd the standard runners I would not gain much as the webbing already lets my butt sit on the tub floor. You will gain something but I would disagree with Tony on the figure of 7/8 inch. Certainly a gain but exactly how much I could not guarantee. Without any form of pad under your butt you will notice a ride difference as I have tried it.

For those harness bolts, use dome headed bolts and the effect is reduced.

JP · 02-13-04, 08:12 AM

The easiset solution is buy an MDA. Mark Sibley, owner, is a solid guy. He has designed the short comings out of the GTD - no punn intented!

His details: www.gt40uk.com

Regards,

J.P

jimbo · 02-13-04, 11:17 AM

You guys are being a little rough on yourselves..the issue is height, not weight. For short fat guys like me, the issue is being flexible enough to get in and out of a GT40. I'm the right height (5'8") but the wrong weight (175+). However, if there's any car in the world I will go on a diet for, it will be this one. Besides, after I finish paying for it, I won't be able to afford to eat, so the problem will solve itself. [img]/ubbthreads/images/graemlins/grin.gif[/img]

Howard Jones · 02-13-04, 01:57 PM

I'm 5'2" and 180lb and I fit fine. I took out the runners, to mount the seat farther forward, and gained about a inch in overhead clearance. Also the center consol should be made as narrow as possible. Mine is a center shift, USA, and it is 3" wide.

The peddles can be made to fit your feet better if you trim off the sides of the foot pads between the brake and clutch. This will leave you with a little narrower pads but it will work ok. then you can bend the gas peddle over to the right by putting a kink in the arm.

I looked at the steering shaft mount in my car and I'm sure there is something to be gained there also with a little thinking. Maybe another inch or so.

If your butt still don't fit then it's diet time.

JOSEPH · 02-13-04, 01:59 PM

Maybe Brian McCarthy can help out. He is building a GTD in New Hampshire and is a really big guy. Or maybe you could put the seat a little towards the center which would aline you up to the peddles. Also the seats in CAV's have bolts that go through the floor and thighten from under the car floor. I took the " foot " off the back bolts which put the back of the seat right on the floor. I then raised the front of the seats up about 2" which made it tilt back and gave me more support under my legs. Lowering the back also gave me about 3 fingers of head room. I'm 6' 1" and this really made the seats much more comfortable. Joe [img]/ubbthreads/images/graemlins/grin.gif[/img]

Frank Catt · 02-13-04, 05:28 PM

In the 60s Colin Chapmen designed the Lotus 40 as a replacement for the very unloved Lotus 30 - it quickly became known as the Lotus 30 with 10 more faults !

Paul Thompson 'Hooligan' · 02-13-04, 06:45 PM

Simon -

Have no fear! - I always remember climbing out of Roy's GTD in the top paddock at Wiscombe to the amazement of the marshalls who could not believe I fitted. (5-11 / 250+lbs)
In fact they asked me to get back in just to prove it! (bloody cheek)

On another note - I recommend you always wear suitable footwear - preferably race boots as the last thing you want is you feet getting tangled when you most need to brake!

Me at SPA 2001

Jools · 02-13-04, 08:18 PM

Paul can not only fit in to drive a 40 , he has been seen on numerous occasions upside down,feet sticking out of the roof ,head under the dash with a soldering iron gritted between his teeth!! Nothing to do with the electrics of course ...he just likes it!! To be fair he's sort of a reverse Tardis [img]/ubbthreads/images/graemlins/grin.gif[/img]....And he still keeps winning races.. I'm not bitter [img]/ubbthreads/images/graemlins/mad.gif[/img]

Chris E · 02-13-04, 08:36 PM

Mines a KVA so maybe things are different, but I've solved the problem by:
- cutting out the front of the footwell,
- moving the pedals forward so that they are 4" further forward than would have been possible without extending the footwell,
- repositioning the rack - checking that the geometry is still OK.
- removing the seat runners to lower the seat
- raising the steering column by removing the 1/2 inch of fibreglass just below the rev counter

I haven't quite finished the mods yet so haven't driven the car, but I reguarly have a sit in it and make brrrm brmmm noises and all seems OK without needing a Gurney dome.

I'm 6'4" and similar weight to Paul - maybe a little bit less, maybe a little bit more!!
[img]/ubbthreads/images/graemlins/blush.gif[/img]

Bigend · 02-13-04, 09:57 PM

I know a very good orthopaedic surgeon.........

gt40rick · 02-14-04, 01:37 AM

As some of you may know Bud Jones lowered the floor in my car by 1/2", raised the body of the car by 1/2" and moved the pedals foward before I bought the car from him. I am 6'2" about 230lbs and fit just fine.

David Morton · 02-14-04, 04:37 AM

My GTD is set up with a maximum height of 6ft 1" approximately. I'm 5ft 11" so I use my pedals on the fully rearward position and my seat back slightly raised away from the rear bulkhead. I do not use the GTD steering rack
and the steering wheel is detacheable (from Racetech).
The seats themselves are in two parts and the bottom section is none adjustable. Harness system is Sabelt six point. Tony Hunt has tried the car for size and he fits in
OK. I guess Tony is about 6ft 1" plus.
Dave M

Tony Hunt · 02-14-04, 06:56 AM

Malcolm,
[ QUOTE ]
My seats are on runners. They are GTD supplied seats. You will gain something but I would disagree with Tony on the figure of 7/8 inch. Certainly a gain but exactly how much I could not guarantee

[/ QUOTE ]
I quoted not 1" nor 3/4" because I gained 7/8" when I removed my runners. Believe me, you can come and measure it!
Good idea about the dome-head bolts though.

Simon · 03-24-04, 04:28 AM

I have removed the seat runners on the drivers seat which has dropped it about an inch. I can now sit in the car comfortably with room to spare over my head. The only thing I have between me and the floor though is the padding of the seat. (oh... and the ample padding in my backside!) having not driven any great distance, I can't tell you if it's a problem.
I left the runners on the passenger seat so if anyone wants a picture for comparison, let me know.
Simon

Tony Hunt · 03-24-04, 06:08 AM

[ QUOTE ]
I have removed the seat runners on the drivers seat which has dropped it about an inch. I can now sit in the car comfortably with room to spare over my head. The only thing I have between me and the floor though is the padding of the seat. (oh... and the ample padding in my backside!) having not driven any great distance, I can't tell you if it's a problem.

[/ QUOTE ]
I found that I ended up sitting on the head of the crutch-strap bolt, which was amply painful after 5 minutes in the garage!
Fortunately my GTD has a 6-point harness mounted as a 5-point, the 2 crutch straps going to the common bolt in the middle. So I plugged up the hole with a grommet, bought another bolt, nut and a number of washers and drilled 2 new holes each side, just inboard of the seat mountings, on a parallel with the old hole. The washers served both to spread the loads into the floor and to lift the strap buckle off the carpet, making adjustment of crutch-strap length, without removing the seat, possible for the first time.
I'm still sitting on the floor though, and will have to see whether NBS (numb bum syndrome) needs padding between seat and floor.
So, I still need a Gurney Bubble, but can at least sit in the car with my head upright, albeit jammed against the roof.

Peter D · 03-24-04, 07:52 AM

And I thought the phrase "lift & separate" only applied to ladies' bra's !!!!

Peter D.